How to Repair Metal Roof Leaks with Super Silicone Seal

To repair a leaking metal roof seam with Super Silicone Seal, first identify where water is entering, secure loose panels, and prepare a clean, dry surface. The repair uses Super Silicone Seal and polyester fleece to seal the seam. This guide and demonstration video explain surface preparation, fastening, and application so you can address the source of the leak.

Super Silicone Seal provides a flexible, UV-resistant seal for metal roof repairs. It can remain exposed to sunlight without a protective topcoat. However, paint will not adhere to the silicone, so consider the finished appearance before applying it.

5 Mistakes to Avoid When Repairing Metal Roof Leaks

• Expecting a roof coating to fix leaks: Coating the entire roof is not a substitute for finding and repairing the source of a leak. First, locate and repair leaking seams, loose screws, and failed flashing. A coating will not tighten loose fasteners or secure separated seams. Repair first—then consider whether the roof needs a coating.
• Using household caulk: Avoid ordinary household caulk when repairing metal roof seams or sealing roof screws. Use a sealant designed for roofing repairs and compatible with the surface.
• Patching seams with roofing tar: Tar can dry out and crack over time, allowing leaks to return. For the repair shown here, remove old tar from the repair area before applying Super Silicone Seal and polyester fleece.
• Leaving screws loose: Tighten loose screws securely. If a screw spins without tightening, replace it with a suitable roofing screw of a larger diameter so it grips firmly.
• Stepping on raised metal ribs: Avoid stepping on the raised ribs of the metal roof panels. This can crease the metal, leading to cracks and leaks.

This guide focuses on repairing metal roof seams with Super Silicone Seal and polyester fleece. Remove old tar and asphalt from the repair area before applying the product. The surface must be clean and completely dry.

How to Repair Metal Roof Seams with Super Silicone Seal

1. Locate the source of the leak: Inspect the seams, screws, and nearby flashing to identify where water is entering. Remove old repair material as needed to expose the problem before deciding where to apply Super Silicone Seal.
2. Remove old repair material: Use a flat bar, claw hammer, or trowel to carefully remove hardened tar and loose repair material from the seam without damaging the metal panels. Expose the area that needs repair.
3. Clean the bonding area: Remove remaining tar, loose paint, and silicone caulk from the metal where the repair must bond. Use an angle grinder fitted with a wire brush where needed, taking care not to damage the metal. Firmly attached silicone roof coatings can remain after cleaning and drying.
4. Wipe clean and allow to dry: Where needed, use a rag dampened with lacquer thinner to remove remaining residue from the metal bonding area. Follow the cleaner’s label instructions and keep it away from sparks and flames. Allow the solvent to evaporate completely. The surface must be clean and completely dry before applying Super Silicone Seal.
5. Secure loose panels and screws: Tighten loose screws so the metal panels stay securely joined at the seam. If a screw spins without tightening, replace it with a suitable roofing screw of a larger diameter so it grips firmly. Complete these repairs before applying the sealant.
6. Stir and apply the first coat: Stir Super Silicone Seal thoroughly before use. Using a paintbrush, apply the first coat over the prepared seam, extending at least 2 inches onto each side. Coat an area slightly wider than the polyester fleece so its edges will sit in sealant.
7. Embed the polyester fleece: Place the fleece into the wet first coat, centered over the seam. Press it into the sealant with your brush, smoothing out wrinkles and trapped air. Where fleece pieces join, overlap them by at least ½ inch, with Super Silicone Seal between the overlapping layers.
8. Apply the topcoat immediately: After embedding the polyester fleece into the wet first coat, apply a second coat of Super Silicone Seal over it. Cover the fleece completely, leaving no exposed fabric.
9. Check the repair on sloping surfaces: Inspect the repair after 30–40 minutes. If the silicone has flowed away and exposed any fleece, apply additional Super Silicone Seal to cover the fabric completely.

On a warm day, allow about 30 minutes before rain exposure. Below 32°F, allow 3–4 hours. Rain readiness differs from full curing: Super Silicone Seal takes about 24 hours to cure fully under suitable conditions, and cold weather can extend this time.

Frequently Asked Questions About Metal Roof Leak Repair